20706 has 32 divisors (see below), whose sum is σ = 51840. Its totient is φ = 5376.

The previous prime is 20693. The next prime is 20707. The reversal of 20706 is 60702.

20706 is nontrivially palindromic in base 5.

20706 is a nontrivial binomial coefficient, being equal to C(204, 2).

It is a Curzon number.

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (20707) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 700 + ... + 728.

It is an arithmetic number, because the mean of its divisors is an integer number (1620).

2²⁰⁷⁰⁶ is an apocalyptic number.

20706 is the 203-rd triangular number and also the 102-nd hexagonal number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20706, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25920).

20706 is an abundant number, since it is smaller than the sum of its proper divisors (31134).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20706 is a wasteful number, since it uses less digits than its factorization.

20706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58.

The product of its (nonzero) digits is 84, while the sum is 15.

The square root of 20706 is about 143.8957956300. The cubic root of 20706 is about 27.4598864193.

The spelling of 20706 in words is "twenty thousand, seven hundred six".